RPM Technik 911 CSR: Review

Take a 997 Carrera, sprinkle with fairy dust and build yourself a cut-price GT3 chaser - with four seats!

"As happy going flat through Eau Rouge as it is pottering off to Café Rouge and all at a budget you can afford." So goes the sales pitch for the 997 Carrera-derived CSR from Hertfordshire-based Porsche specialist RPM Technik.

Nothing lairy but intent is clear enough

"We understand that even in this sector it is not always within people's budget to have separate track day and road cars. And that Porsche's purpose built track cars, superb as they are, don't always come equipped with driver comforts, or even rear seats. They are often fitted with cage, race seats and harnesses too so perhaps not ideal for going out to dinner in!"

So says Darren Anderson, passionate Porsche man who, together with colleague Ollie Preston and the team at RPM Technik, has created a thriving business maintaining, selling and now fettling Stuttgart's finest over the last 12 years.

The company has strong sales and servicing departments but it is also known for its fleet of track-prepped machines including a 911 SC, Boxster racer, 944 Clubsport and 996 GT3. Their cars can be hired for track events and they offer full prep and customer support for customer cars and race programmes.

No power boost claimed but razor sharp response

Balancing actThe CSR is RPM Technik's attempt to blend performance and practicality to create the perfect balance between road and track capability. A balancing act that is pretty much the Holy Grail for sports car tuners everywhere and with extensive development at the 'ring and Millbrook, the company thinks it has it bang on.

The base car is a first-gen 997 Carrera S, a car that can be picked up for around the £20K mark these days. From there, RPM has paid detailed attention to every aspect of the machine in creating the CSR.

There is something just right about the car's stance. It looks low and wide over superlight OZ alloys and the carbon fibre ducktail is an immediate head turner. The jawline differs, too, thanks to a modified Turbo front bumper - the foglights now indicators.

Ducktail is a subtle but effective calling card

Creature comfortsInside there are few bits of matt black trim giving a stealth feel to the interior, along with a red CSR dial taking centre stage. Overall, though, it is pretty much as Porsche intended. No cage, no harnesses, rear seats in situ, pretty normal and nicely comfy.

This car is fitted with a fairly tame exhaust system today to ensure compliance with Bruntingthorpe's strict noise limits. "It's a shame," says Darren, "because the full sports system sounds brilliant and gives the car a much harder edge to the engine note as well as more volume."

There are some terrific back roads in the vicinity so before we take our allotted slot on the proving ground, we try out the CSR's on-road credentials. It takes about 100 yards to realise that this is quite an evolution from a standard 997.

Stance underlines chassis work beneath

Reaction timeThe engine feels instantly more responsive and the gearchange requires a bit more concentration, thanks to the lightweight clutch and flywheel. The steering has considerably more weight than the standard car, thanks to the new suspension and those tacky Yokohama tyres. Heftier, yes, but full of feel and feedback.

The ride is firm but not unacceptably so. "We tend to offer three different set-ups: road, fast road or track," explains Darren. "This is what I'd call fast road. We have done quite a bit of track work with it but I have also driven it to and from Spa so I didn't want it to be unbearable. If a customer does more track work, we can set up the suspension to suit. If they want a more compliant setting and a bit more ride height, that is not problem."

The suspension is an Ohlins system, fully adjustable, and the car gets poly bushes, uprated anti-roll bars and then gets a full geometry setup and corner weights checked to ensure optimum performance. The wheels reduce unsprung weight considerably and the brakes are standard discs and calipers but get new pads. "They are more than up to the job on road and track."

Needle fair zings around rev counter with mods

Flatters to deceiveThe engine feels brawny: although there is nothing major in the rework under the ducktail, RPM has fitted a high-flow air filter to complement the new exhaust and lightened and balanced the crank. The company isn't claiming a horsepower boost but the 3.8-litre unit seems more responsive and the mid-range feels especially strong. It also revs out with gratifying ease, and you have to keep half an eye on the tacho to avoid the limiter before you get used to it. It's hard to believe there isn't an extra 20-30hp from this blueprinted unit.

The inclusion of a Wavetrac torque vectoring limited-slip differential is one of the more notable things on the CSR spec sheet too. "We have done a lot of testing and we felt this gave us the best combination of handling characteristics, optimising the car on track without sacrificing anything on the roads," says Darren.

Front-end grip matched with epic traction

On the noseThere is certainly a terrific front end on the CSR. It really handles 'on the nose' and that in turn gives great confidence. But there is no sense that the rear of the car is going to get lairy, even when braking deep into a corner.

At Bruntingthorpe we could push that handling to the limit and beyond and the CSR impressed from lap one. Grip levels on hot tarmac are phenomenal and the Wavetrac diff gives a really sweet, neutral feel to cornering. The front bites, you sense the beginning of a rotation towards the rear, sitting the car over its fat rear boots but then it really digs in and fires your out of the turn, reluctant to relinquish its grip on the asphalt.

It is pretty difficult to induce understeer in this car without quite serious provocation. Mind you, it is also fairly reluctant to oversteer. A bit of a lift will do it and really piling on the power will, too. But in general slides are small, well telegraphed through the steering and easily caught. This car is keen to record rapid lap times rather than vaporise its rear boots.

Spangly OZs trim some valuable unsprung kilos

High speed stability is impressive and the brakes proved resistant to fade over several hard laps. It's easy to imagine the CSR is a bit of a giant killer on track days - especially circuits where chassis set-up is more important than big power outputs.

And what of the GT3?It's a tricky old balancing act, combining road and track performance but the CSR manages to pull it off pretty convincingly. And the beauty of the CSR package is that you can really pick and choose what you want. RPM Technik will happily source you a 997 and produce a fully-finished CSR, including build plaque if you want that. Or, if you already have a 997, you can dip in at whatever level you fancy. So if you just want the suspension, that's fine - £2,340 plus VAT and fitting. Love the ducktail? No problem - £1,400 plus VAT.

CSR realises added potential in stock Carrera

One wonders whether you'd really opt for the CSR over a GT3 but that ability to build your CSR over time and when budget allows makes a lot of sense. And honestly, it really does offer a driving experience worthy of comparison and without some of the compromises. Whether it'll have the status, long term collectability or resale potential of a GT3, however...

But it's a thrill ride, the CSR, no doubt about it, and it takes the stock 997 to a whole new level for driving pleasure and involvement. It looks good, goes better and as summer evening drives go, the one spent at the wheel of the CSR will be remembered for a long time to come.